Juvenile Common Carp Cyprinus Carpio Research Articles

Study of the diets of two coexisting species – invasive Chinese sleeper (Perccottus glenii Dybowski, 1877) and native European perch (Perca fluviatilis Linnaeus, 1758)

In Poland, the Chinese sleeper Perccottus glenii is one of the alien fish species which, by effectively competing with native species, may contribute to the weakening of their population and a reduction of the biodiversity. The aim of this paper is to study the diets of two coexisting species: the native European perch Perca fluviatilis and the invasive Chinese sleeper. The fish were collected from a watercourse used for draining water from a fishing farm, located in the Nida River water system (Poland), using the electrofishing method. The captured fish were killed, preserved in a 4% formaldehyde solution and the stomachs of the fish were dissected. Then, based on the materials collected from these stomachs, the abundance and taxonomic rankings of the individual diet components (quantity of individuals in the individual taxa) were determined. The overlap of the P. fluviatilis and P. glenii feeding spectra was studied using a principal component analysis (PCA). The analysis of the data collected demonstrated that the diets of these two species overlaps considerably. At the same time, the analysis of the major diet components showed that the niche used by P. fluviatilis is broader than that used by P. glenii. It seems that, due to its high level of plasticity, P. fluviatilis is able to withstand the pressures of P. glenii and is also able to limit its abundance. Both species frequently choose fish as their prey, including juvenile common carp Cyprinus carpio Linnaeus, 1758, which indicates that together with native predators, P. glenii may pose a considerable threat to farmed juvenile Cyprinidae.

Transcriptome analysis reveals the mechanisms of hepatic injury caused by long-term environmental exposure to atrazine in juvenile common carp (Cyprinus carpio L.).

Atrazine (ATZ) is the second most commonly used herbicide worldwide, resulting in the pollution of water bodies and affecting the economic benefits of aquaculture. ATZ is known to cause liver damage in the common carp, Cyprinus carpio L., one of the most widely cultivated fish in China, but the underlying mechanisms are poorly understood. In this study, juvenile common carp Cyprinus carpio L. were exposed to three different environmental levels (0.4, 0.8, and 1.2μg/L) of ATZ for 12weeks and changes in the liver transcriptomes between the high-dose group and the control group were analyzed. The data showed that different levels of ATZ exposure caused hepatotoxicity in juvenile carp, shown by biochemical parameters and histopathological changes. Comparative transcriptomics showed that high-dose ATZ exposure led to alterations in the expression of various lipid metabolism-related gene changes, including genes associated with metabolic pathways, fatty acid metabolism, and fatty acid elongation. Furthermore, a connection network analysis of the top 100 differentially expressed genes (DEGs) showed a variety of associations between high-dose ATZ-induced liver damage and the principal DEGs, indicating the complexity of hepatotoxicity induced by ATZ. In conclusion, the molecular mechanisms underlying ATZ-triggered hepatotoxicity in juvenile carp are primarily related to impaired lipid metabolism.

Effect of Greater Duckweed Spirodela polyrhiza Supplemented Feed on Growth Performance, Digestive Enzymes, Amino and Fatty Acid Profiles, and Expression of Genes Involved in Fatty Acid Biosynthesis of Juvenile Common Carp Cyprinus carpio

The greater duckweed Spirodela polyrhiza (Lemnaceae) is a free-floating freshwater macrophyte. The effect of dietary inclusion of duckweed in the feed of common carp Cyprinus carpio fry was evaluated. The control feed (SP0) contained soybean meal as the primary protein source. In four experimental feeds, greater duckweed was incorporated at levels of 5% (SP5), 10% (SP10), 15% (SP15), and 20% (SP20) replacing soybean meal. Broken-line regression showed that incorporation of greater duckweed at 10 and 13.4% levels were the breakpoint for final weight and specific growth rate (SGR) of fish, respectively. The final weight and SGR of common carp fed diet SP20 were significantly higher compared with those of others. The feed conversion ratio was lowest in SP20 treatment. The inclusion of greater duckweed in the fish feeds showed linear relationships with amylase, trypsin, chymotrypsin, and lipase activities. The content of crude protein was significantly higher in SP10, SP15, and SP20 treatments compared with that of others. Significantly higher crude lipid and ash contents were found in SP20 diet-fed fish compared with other diet-fed fish. The essential amino acids composition was similar in five different diet-fed fish. The greater duckweed supplemented feeds influenced the fatty acid contents of fish. The monounsaturated fatty acids (MUFA) showed an inverse relationship with the inclusion level of greater duckweed in the feed. The highest MUFA content was found in fish fed SP0 diet. The highest level of linoleic acid was found in SP20 diet fed fish. The n-3 PUFA contents of fish showed an increasing trend with the increasing inclusion of greater duckweed, and a significantly higher level was found in SP20 compared with that of others. A significantly higher expression of fas was found in SP5 and fads2d6 in SP5 and SP10 compared with that of others. The expressions of elovl2 and elovl5 were significantly higher in SP5, SP10, and SP15 diet-fed fish compared with other diet-fed fish. The incorporation of greater duckweed in diets improved the growth performance and nutritional value of common carp.

Warming alters juvenile carp effects on macrophytes resulting in a shift to turbid conditions in freshwater mesocosms

Abstract Multiple stressors such as climate change and eutrophication are responsible for the global decline in macrophytes in lakes. The loss of this key component can result in turbid conditions and a loss of important ecosystem functions and services, particularly in shallow lakes. Benthivorous fish, which can increase in abundance during eutrophication, can adversely affect macrophytes through physical disturbance, cascading effects on turbidity, suspended and attached algae (phytoplankton and periphyton) and direct consumption. However, whether warming amplifies their effects on macrophytes and can trigger regime shifts remains unexplored. Here, we tested the single and combined effects of warmer water (+4.5°C) and the widespread benthivorous juvenile common carp Cyprinus carpio on two different types of aquatic macrophytes in 24 mesocosms (2,500 L each). We monitored phytoplankton, periphyton, turbidity and the abundance of the submerged curly leafed pondweed Potamogeton crispus and the floating‐leaved water chestnut Trapa bispinosa during their growing season. These species dominated successively in spring and summer. Warming alone advanced the growing season of P. crispus by 17 days. Juvenile carp decreased the abundance of the more palatable P. crispus, but promoted the abundance of T. bispinosa, supporting an ecosystem shift to a dominance of floating‐leaved macrophytes. Fish also substantially increased water turbidity and the biomass of phytoplankton and periphyton. Warming amplified juvenile carp effects on turbidity and submerged macrophytes, but also decreased the abundance of floating‐leaved macrophytes leading to an overall macrophyte decline and increase in water turbidity. Synthesis and applications. Our study provides the first experimental evidence for a warming‐induced regime shift from clear‐water conditions dominated by submerged or floating/floating‐leaved macrophytes to a turbid state in shallow aquatic ecosystems. The regime shift was triggered by the impacts of warming on benthivorous fish (juvenile common carp) rather than on macrophytes. Lowering nutrient loading and other measures to reduce the abundance of benthivorous fish (e.g. fish removal and piscivorous fish restocking) thus may become increasingly important for the management of shallow lakes under global climate change.

Dietary immunostimulants reduced infectivity of Diplostomum spp. eye fluke in common carp, Cyprinus carpio L

Juvenile common carp Cyprinus carpio L. (5.52 ± 1.66 cm, TL) were fed on four diets containing either beta-glucan (MacroGard, 1 g kg −1), nucleotides (Optimûn, 0.2 g kg - 1), chitosan (deacetylated chitin ≥75% shrimp shells, 10 g kg −1) or a basal control diet for 35 days to test whether these so-called “immunostimulants” could affect eye fluke Diplostomum spp. infection success. The immunostimulants diets reduced the number of eye fluke infecting the eyes of C. carpio, with significantly higher infections in the control diet (4.78 ± 1.27) compared with the chitosan (2.08 ± 0.87), nucleotide (2.98 ± 1.01), and beta-glucan (1.41 ± 0.79) diets. To our knowledge, this is the first study to provide evidence that beta-glucan, nucleotides, and chitosan diets can aid against a Diplostomum infection and provides valuable preliminary knowledge on the use of immunostimulants to ameliorate parasitic infections.

Effect of Melatonin on the Processes of Exotrophy in Common Carp Cyprinus carpio

The effect of melatonin on the initial (feeding) and central link (digestion) of exotrophy in juvenile common carp Cyprinus carpio was investigated in parallel for the first time. The effect of intraperitoneal injections of the hormone at a concentration of 100 and 200 ng/g of body weight on locomotor activity and food consumption, as well as on the activity of digestive enzymes in the intestinal mucosa and chyme, was studied. It was shown that five hours after the administration of the hormone, food consumption and the activity of digestive enzymes in the intestinal mucosa decrease, while the locomotor activity of fish and the enzymatic activity of the chyme do not change significantly. Food consumption is significantly (by factor of 2.2) reduced as a result of the administration of the hormone at a dose of 200 ng/g body weight. The level of caseinolytic and hemoglobinolytic activity of peptidases and amylolytic activity of the intestinal mucosa at this dose also decrease significantly: by 27, 54 and 42%, respectively, compared to the control. The injection of melatonin at a dose of 100 ng/g causes a slight decrease in the level of enzymatic activity of the intestinal mucosa. The mechanisms of the effect of melatonin on the processes of exotrophy in fish are discussed.

Short-Term Starvation Changes the Sensitivity of Intestinal Glycosidases of Juvenile Common Carp Cyprinus carpio L. to an Increase in the Water Temperature

The activity of glycosidases (maltase activity and amylolytic activity) in the intestinal mucosa of juvenile common carp Cyprinus carpio (L.) under a sharp increase in water temperature depends on its physiological state (satiety or starvation). The fish are acclimated to a temperature of 22°С during the summer (young-of-the-year) and winter (yearling) seasons. An increase in water temperature at a rate of 8.0°C/h leads to an increase in amylolytic activity in well-nourished fish, but the maltase activity does not change. Starving for 3 or 10 days changes the response of glycosidase to temperature stress: the maltase activity increases, but amylolytic activity does not change. Short-term starvation does not affect the thermal tolerance of juvenile common carp; i.e., the values of the critical thermal maximum in hungry and well-nourished specimens do not differ.

Growth, survival and immune responses of juvenile common carp Cyprinus carpio fed with diets enriched with α- tocopheryl acetate

Cyprinus carpio is a popular food fish species and is stocked regularly in reservoirs of Sri Lanka. However in semi-intensive aquaculture, growth and survival of this species are very low resulting in high production cost. The present study was carried out to determine the growth, survival and immune enhancement to pathogenic Aeromonas hydrophyla of juvenile common carp fed with tocopheryl acetate augmented formulated feed. Experimental set up included four treatments each with three replicates arranged in completely randomized design. Initial total weight of the experimental individuals ranged from 200 to 320 g. Experimental fish, which were stocked in 150 cm x 150 cm x 60 cm cement tanks were fed twice a day. The four treatments were; non-enriched commercial feed (T1), non-enriched formulated feed (T2), formulated feed enriched with Tocopheryl Acetate (TA) 2 mg (T3) and formulated ration enriched with TA 4 mg (T4). After the end of the feed trial, experimental animals were exposed to 5 ppm A. hydrophila concentration for 5 minutes duration. The highest Specific Growth Rate (SGR) (1.21) was observed in treatment T4, followed by Control treatment T1 (1.16), which were not significantly different from T3 (1.11). The lowest SGR (1.04) was recorded for T2. The highest (93%) and the lowest (69%) survival were observed in T4 and T3 respectively. The lowest Food Conversion Ratio (FCR) (1.61) was also observed in T4. In T3 and control, they were 1.93 and 1.96 respectively. The highest FCR was also observed in T2 (2.14). No mortality was recorded in T4 after exposing to bacteria concentration while it was 20% in T3. The highest percentage mortality (60%) was recorded from T2 followed by the control (40%). Results indicate that enrichment of prepared feed using Tocopheryl Acetate gives a good growth rate, good survival, hence reducing the production cost. Further, results indicate that Tocopheryl Acetate positively enhances the immunity of the experimental fishes to Aeromonas infection.

Biochemical responses over time in common carp Cyprinus carpio (Teleostei, Cyprinidae) during fed supplementation with α-lipoic acid

The current study aimed to evaluate the influence of lipoic acid (LA) supplementation (439.84±6.71mg LA/kg feed) on antioxidants responses throughout the time in intestine, liver and muscle of juvenile common carp Cyprinus carpio. Two experimental groups were fed during four weeks with a diet with or without LA. Glutathione-S-transferase (GST) activity, glutathione (GSH) content, antioxidant capacity against peroxyl radicals (ACAP) and lipid peroxidation (TBARS) were evaluated in these organs. Also, a technique to measure protein disulfide bonds and sulfhydryl groups was optimized for intestine samples. GST activity was significantly higher (p<0.05) in intestine after two weeks of supplementation. GSH content was also significantly higher (p<0.05) in intestine, liver and muscle of fish fed with LA after two and three weeks, respectively. Total capacity antioxidant against peroxyl radicals was significantly increased (p<0.05) in the muscle of animals fed with LA after the fourth week. Concentration of disulfide bonds was higher in the intestine of fish fed with LA but this group also showed higher concentration of sulfhydryl groups (p<0.05). It is concluded that supplementation with LA is a safe strategy to induce antioxidant responses and improves the antioxidant status in different organs of common carp. Two week of supplementation are required to induce antioxidant responses in intestine and liver and three week for muscle.

Dietary effect of Quillaja saponaria and/or Yucca schidigera extract on growth and survival of common carp Cyprinus carpio, their antioxidant capacity and metabolic response to hypoxic condition

This study evaluated dietary effects of extracts of Quillay Quillaja saponaria, and/or Yucca Yucca schidigera on growth and survival of juvenile common carp Cyprinus carpio, and their antioxidant capacity and metabolic response to low dissolved oxygen (DO) stress. For 8 weeks, fish were fed one of 4 different diets. The diets were supplemented with either 150 mg/kg Quillay (QS), 150 mg/kg Yucca (YS), the combination of 75 mg/kg Quillay and 75 mg/kg Yucca (M), or control diet (C) without addition of Quillay or Yucca. Growth and survival were monitored periodically. After rearing, fish were subjected to low DO stress, and after a week, antioxidant capacity (superoxide dismutase, glutathione peroxidase and glutathione reductase) and metabolic response (glucose, triglycerides and lactate) were analyzed. QSfed fish had the highest weight gain among all the treatments. Treatments did not affect fish survival a week after low DO stress. Among antioxidant capacity and metabolic response, significant effects were found only on superoxide dismutase and glucose. QS fed fish had 39% lower plasma superoxide dismutase than the C and M groups. QS and M groups exhibited 29% and 26% lower plasma glucose than the C group, respectively. Overall, the QS diet improved growth and exhibited favorable antioxidant capacity and metabolic response of carp to low dissolved oxygen environment.

Dietary effect of Quillaja saponaria and/or Yucca schidigera extract on growth and survival of common carp Cyprinus carpio, their antioxidant capacity and metabolic response to hypoxic condition

This study evaluated dietary effects of extracts of Quillay Quillaja saponaria, and/or Yucca Yucca schidigera on growth and survival of juvenile common carp Cyprinus carpio, and their antioxidant capacity and metabolic response to low dissolved oxygen (DO) stress. For 8 weeks, fish were fed one of 4 different diets. The diets were supplemented with either 150 mg/kg Quillay (QS), 150 mg/kg Yucca (YS), the combination of 75 mg/kg Quillay and 75 mg/kg Yucca (M), or control diet (C) without addition of Quillay or Yucca. Growth and survival were monitored periodically. After rearing, fish were subjected to low DO stress, and after a week, antioxidant capacity (superoxide dismutase, glutathione peroxidase and glutathione reductase) and metabolic response (glucose, triglycerides and lactate) were analyzed. QSfed fish had the highest weight gain among all the treatments. Treatments did not affect fish survival a week after low DO stress. Among antioxidant capacity and metabolic response, significant effects were found only on superoxide dismutase and glucose. QS fed fish had 39% lower plasma superoxide dismutase than the C and M groups. QS and M groups exhibited 29% and 26% lower plasma glucose than the C group, respectively. Overall, the QS diet improved growth and exhibited favorable antioxidant capacity and metabolic response of carp to low dissolved oxygen environment.

Effects of temperature on the foraging and growth rate of juvenile common carp, Cyprinus carpio

Temperature had a significant and positive effect on the foraging and growth of juvenile common carp Cyprinus carpio (90–105 mm) between 16 and 28 °C. Metrics measured were feeding rate (items s −1), functional response (feeding rate as a function of food density), specific growth rate and incremental fork lengths. Experiments that were conducted at 16, 20, 24 and 28 °C and used two food types revealed a strong thermal influence on foraging, with the highest feeding rates achieved at 24 °C. Functional responses also revealed optimal feeding rates in relation to food density occurred at temperatures >20 °C. Specific growth rate and incremental fork lengths were depressed at 16 and 28 °C when compared to those achieved at 20 and 24 °C. These outputs suggest an increase in foraging and growth of C. carpio according to a thermal gradient that were maximal between 24 and 28 °C.

Phenotypic variation and associated predation risk of juvenile common carpCyprinus carpio

Juvenile common carp Cyprinus carpio were collected from 10 lakes with variable predator abundance over 4 months to evaluate if morphological defences increased with increasing predation risk. Cyprinus carpio dorsal and pectoral spines were longer and body depth was deeper when predators were more abundant, with differences becoming more pronounced from July to October. To determine if morphological plasticity successfully reduced predation risk, prey selection of largemouth bass Micropterus salmoides foraging on deep- and shallow-bodied C. carpio was evaluated in open and vegetated environments. Predators typically selected deep- over shallow-bodied phenotypes in open habitats and neutrally selected both phenotypes in vegetated habitats. When exposed to predators, shallow-bodied C. carpio phenotypes shoaled in open habitat, whereas deep-bodied phenotypes occupied vegetation. Although deep-bodied phenotypes required additional handling time, shallow-bodied phenotypes were more difficult to capture. These results suggest that juvenile C. carpio gradually develop deeper bodies and larger spines as predation risk increases. Morphological defences made it more difficult for predators to consume these prey but resulted in higher vulnerability to predation in some instances.

Behavioral alterations in GH transgenic common carp may explain enhanced competitive feeding ability

The aim of the present study was to clarify the role of GH transgenesis and its production in social interactions in juvenile common carp Cyprinus carpio. With food pellets provided sequentially, the serum GH levels and behavioral effects were measured in 14 pairs of size-matched ‘all-fish’ GH-transgenic and non-transgenic common carp. In six consecutive observations during 3 days, transgenic fish had a higher movement level as well as a higher social status, being 2.69 times as aggressive, two minutes before and after the 10-min feeding session compared to non-transgenic fish. Transgenic fish also were more than 1.74 times as likely to consume each pellet. During the 8-day experiment, transgenic fish had 4.09 times higher specific growth rate in body weight as well as 6.36 times higher serum GH level than the non-transgenic fish. These results show that GH transgenesis promotes over-expression of GH and alters behaviors in juvenile common carp, thereby increasing their ability to compete and gain food resources, presumably to meet a higher intrinsic growth rate, which gives direct evidence for the GH-induced elevation in feeding competitive ability of GH-transgenic common carp. Understanding these relationships would not only help evaluating potential ecological effects of the escaped/released transgenic fishes, but also help using potential aquaculture of this growth-enhanced strain.

Effect of acute crowding stress on subsequent osmotic challenge and recovery in juvenile common carp Cyprinus carpio (Linnaeus)

Effect of acute crowding stress (density of 25 g/L for 2 and 4 h) on subsequent salinity (8 g/L) tolerance was investigated in juvenile common carp (Cyprinus carpio). To assess osmoregulatory conditions, blood cortisol, glucose, Na+ and Cl− concentrations were measured at 0, 6, 24 and 72 h after osmotic challenge in three groups: control, and groups stressed for 2 and 4 h. Results indicated typical stress responses after crowding stress. In both stressed groups, cortisol was significantly higher than the control group, but no significant difference was observed within the stressed groups. Additionally, glucose levels increased after crowding stress, and there was a significant increase in the in 4-h group compared with the 2-h group. Ion concentration was not significantly affected by crowding stress. Osmotic challenge led to an increase in cortisol and glucose concentrations in unstressed fish, after 6 h, but in stressed fish, no change occurred in cortisol and glucose levels at this point compared to the pre-challenge values. There was no significant change in cortisol and glucose values at 6, 24 and 72 h after the osmotic challenge between groups. Cortisol and glucose returned to pre-stress values by 72 h following the challenge. In all groups, Na+ concentration significantly increased at 6 h after the osmotic challenge and stayed elevated until 72 h; however, there was no significant difference between groups at any time point. There was no significant difference in Cl− concentrations between groups or sampling time points. These results indicate that the common carp is a hyperosmotic regulator after exposure to saline medium, and acute crowding stress does not impair osmotic stress response.

Evaluation of Propeller-Induced Mortality on Early Life Stages of Selected Fish Species

Abstract The mortality of ichthyoplankton entrained through a scale model of a towboat propeller was evaluated in a large (>2 million L) circulating water channel. Five species of fish (larval shovelnose sturgeon Scaphirhynchus platorynchus, larval lake sturgeon Acipenser fulvescens, the larvae and eggs of paddlefish Polyodon spathula, larval blue sucker Cycleptus elongatus, and juvenile common carp Cyprinus carpio) were tested. Replicate groups of individuals were subjected to one or more shear stress levels (634, 1,613, 3,058, and 4,743 dynes/cm2 (1 dyne = the force that would give a free mass of 1 g an acceleration of 1 cm/s2). Mortality was a linear function of shear stress for all species and life stages. Paddlefish eggs and common carp juveniles were more resistant to shear stress than all larval fish. Smaller larvae (lake sturgeon and blue suckers) experienced higher mortalities (>75%) than larger larvae (shovelnose sturgeon and paddlefish). The conditional mortality (i.e., treatment less control m...